IoCommandStruct can be used to send IO commands to groups
The struct created by this function can be used to set pins on
an IO board. NaN and Inf values are ignored. Setting values
to pins that are not configured to be output pins will be ignored
by the hardware.
Example
io = IoCommandStruct();
io.a1 = 1;
io.b3 = 0.3;
group.send('io', io);